Troponini is a more sensitive marker than creatinine kinase MB isoenzyme of left ventricular dysfunction in patients with acute subarachnoid hemorrhage

Introduction: Electrocardiographic(EKG),wall motion abnormalities, and cardiac arrhythmias have been reported following acute non-traumatic sub-arachnoid hemorrhage(SAH). We prospectively studied the utility of troponin I (TnI) and creatinine kinase MB isoenzyme (CK-MB) as markers for left ventricular (LV) dysfunction following acute SAH. Methods: Patients enrolled within 24 hours of SAH. Patients with a history of coronary artery disease (CAD) were excluded. Serial TnI and CK-MB levels were measured every 12 hours. An echocardiogram (echo) was obtained within 48 hours of SAH. Any patient with an elevated TnI was evaluated for CAD before discharge (cardiac catheterization or stress testing). Patients with and without normal left ventricular function (LVF) on echo were compared. Results: 27 patients were studied; 13 were male. The age was 53 ±12 (range 40-72)years. The majority were Hunt Hess Grade II or III (71%) and Fisher Grade III (85%). Three patients had diffuse (2) or focal (1) left ventricular dysfunction. All 3 had elevated TnI (1.8-4 ng/ml). One [TnI 1.8 ng/ml, CK-MB 10 ng/ml (6%)] had evidence of CAD (adenosine thallium). The other 2 (TnI of 3.5 and 4 ng/ml) had no evidence of CAD (cardiac catheterization and dobutamine echo, respectively) and mildly elevated CK-MB 10 ng/ml (2.8%) and 6 ng/ml (4%). All three patients had improved LVF on repeat echo 2 weeks after SAH. 24 patients had normal LVF. 2 had elevated TnI (8.9 and 4.5 ng/ml) with mildly elevated CK-MB 22 ng/ml(3%) and 14 ng/ml (4%) respectively. The first patient died prior to evaluation for CAD. The second had an inferior akinetic segment on dobutamine echo. The remaining 22 had normal TnI (<0.4 ng/ml) and normal or mildly elevated CK-MB (range <0.6-4%). TnI was more sensitive (100% vs. 33%), but less specific (92% vs. 100%) than CK-MB in detecting LV dysfunction. Conclusions: TnI appears to be more sensitive than CK-MB in detecting LV dysfunction in acute SAH. We speculate that in SAH patients, TnI could be used as an adjunctive screen for LV dysfunction prior aneurysm surgery.